Lower Triangular Matrix
A triangular matrix L of the form
Written explicitly,
![画像: L=[a_(11) 0 ... 0; a_(21) a_(22) ... 0; | | ... 0; a_(n1) a_(n2) ... a_(nn)].](/index.cgi/contrast/https://mathworld.wolfram.com/images/equations/LowerTriangularMatrix/NumberedEquation2.svg){kind=link}
A matrix m can be tested to determine if it is lower triangular in the Wolfram Language using LowerTriangularMatrixQ [m].
A strictly lower triangular matrix is a lower triangular matrix having 0s along the diagonal as well, i.e., a_(ij)=0 for i<=j.
See also
Strictly Lower Triangular Matrix, Triangular Matrix, Upper Triangular MatrixExplore with Wolfram|Alpha
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References
Ayres, F. Jr. Schaum's Outline of Theory and Problems of Matrices. New York: Schaum, p. 10, 1962.Referenced on Wolfram|Alpha
Lower Triangular MatrixCite this as:
Weisstein, Eric W. "Lower Triangular Matrix." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/LowerTriangularMatrix.html